A good reminder that your emergency fund should be held in cash at a bank, not in shares a brokerage. Not that a glitch like this couldn’t block access to your bank account too, but rather that the process of liquidating and transferring securities is much slower than ACH or Zelle.
A glitch prevented her account from being displayed for a few days, then was resolved. Your money, when covered via FDIC/SIPC and federal regulations, doesn’t just “disappear”.
If someone else can freeze, deny, censor, or condition your access to your money, then your "ownership" is incomplete, and definitely, not yours.
Never let cash go away. Never.